The Killer (in French, Tueur sans gages) was written in 1957 and had its world premiere in Paris in 1959. It is the first of Ionesco's four plays featuring the hapless, inadvertently heroic Everyman-character Berenger (the other three are A Stroll in the Air, Exit the King and his most popular play, Rhinoceros).

In The Killer, Berenger discovers a "radiant city," a kind of utopia near his dismal urban home. It is a perpetually sunny, impeccable, clean place full of marvelous architecture and beautiful gardens. But there is one hitch: a serial murderer has been killing people for so long that the authorities have given up trying to catch him.